In a study of academic procrastination, researchers reported that for a random sample of 41 undergraduate students preparing for a psychology exam, the mean time spent studying was 11.9 hours with a standard deviation of 4.5 hours. Compute a 95% confidence interval for μ, the mean time spent studying for the exam among all students taking this course.

Answers

Answer 1

Answer:

The 95% confidence interval is  [tex]10.5 < \mu <13.3[/tex]

Step-by-step explanation:

From the question we are told that

     The  sample size is  [tex]n = 41[/tex]

      The  sample mean is  [tex]\= x = 11.9 \ hr[/tex]

       The standard deviation is  [tex]\sigma = 4.5[/tex]

For  a  95% confidence interval the confidence level is  95%

Given that the confidence level is 95% then the level of significance can be mathematically represented as

                  [tex]\alpha = 100 - 95[/tex]

                  [tex]\alpha = 5 \%[/tex]

                  [tex]\alpha = 0.05[/tex]

Next we obtain the critical values of  [tex]\frac{\alpha }{2}[/tex] from the normal distribution table

     The values is

                             [tex]Z_{\frac{\alpha }{2} } = 1.96[/tex]

Generally the margin of error is mathematically represented as

                             [tex]E = Z_{\frac{\alpha }{2} } * \frac{\sigma }{ \sqrt{n} }[/tex]

substituting values

                           [tex]E = 1.96 * \frac{ 4.5 }{ \sqrt{41} }[/tex]  

                           [tex]E = 1.377[/tex]

The 95% confidence interval is mathematically represented as

          [tex]\= x - E < \mu < \= x - E[/tex]

substituting values

         [tex]11.9 - 1.377 < \mu <11.9 + 1.377[/tex]

         [tex]10.5 < \mu <13.3[/tex]


Related Questions

Find a • b. a = 5i + 7j, b = -4i + 3j

Answers

Answer:

[tex]a \cdot b = 1[/tex]

Step-by-step explanation:

[tex] a = 5i + 7j [/tex]

[tex] b = -4i + 3j [/tex]

[tex] a = a_xi + a_yj [/tex]

[tex]b = b_xi + b_yj[/tex]

[tex] a \cdot b = a_xb_x + a_yb_y [/tex]

[tex] a \cdot b = (5)(-4) + (7)(3) [/tex]

[tex] a \cdot b = -20 + 21 [/tex]

[tex]a \cdot b = 1[/tex]

Answer:

[tex]\boxed{-20i^2 -13ij+21j^2}[/tex]

Step-by-step explanation:

[tex]\sf Plug \ in \ the \ values.[/tex]

[tex](5i+7j) \cdot (-4i+3j)[/tex]

[tex]\sf Expand \ brackets.[/tex]

[tex]5i(-4i+3j)+7j(-4i+3j)[/tex]

[tex]-20i^2 +15ij+-28ij +21j^2[/tex]

[tex]\sf Combine \ like \ terms.[/tex]

[tex]-20i^2 -13ij+21j^2[/tex]

Lori wants to buy a radio for 60 dollars.
She can pay $60 now, or she can pay $12
a month for 6 months. How much more will
she pay for the radio if she makes monthly
payments?

Answers

Answer:

Lori will pay $12 more if she makes monthly payments

Step-by-step explanation:

to find how much she will pay for 6 months, we have to multiply 12 by 6 to get $72

subtracting the amount she would pay as a down payment

$72 - $60 is $12

Lori will pay $12 more if she makes monthly payments

Do numbers below 0 make sense outside of the context of temperature? If you think so, give some examples to show how they make sense. If you don’t think so, give some examples to show otherwise.

Answers

Answer:

Yes, they make sense outside the context of temperature.

Step-by-step explanation:

If you are standing in a line, and mark your current position as 0 then if you take two steps ahead it can be counted as positive and if you take two steps back from your current position it can be counted as negative. The positive and negative can denote your forward and backward movement respectively.

If we denote the growth in companies revenue as positive and dip as negative then it would also make sense. A positive number would mean profit for the company while a negative sign would show loss.

Complete the table using the equation w = m + 4

Answers

Answer:

5+4 = 9

6+4 = 10

7+4 =11

Step-by-step explanation:

Answer:

(5,9)

(6,10)

(7,11)

Step-by-step explanation:

w = m + 4

when m = 5,

w = 5 + 4 = 9

when m = 6

w = 6 + 4 = 10

when m = 7

w = 7 + 4 = 11


What is the expression

Answers

Answer:

3

Step-by-step explanation:

z - 2x

--------

y

Let x = 3  y = -4 and z  =-6

-6 - 2(3)

--------

-4

-6 -6

---------

-4

-12

-----

-4

3

Answer:

3

Step-by-step explanation:

To solve this, we need to plug in each of the numbers to the equation.

x = 3, y = - 4, z = - 6

[tex]\frac{z-2x}{y} = \frac{-6-2(3)}{-4}[/tex]

Let's solve the parenthesis first. - 2 * 3 = - 6.

[tex]\frac{-6-6}{-4}[/tex]

We then subtract -6 - 6.

[tex]\frac{-12}{-4}[/tex]

Then, we divide (cancel out the negatives).

[tex]-12 / -4 =3[/tex]

Our final answer is 3. Hope this helps!

The sum of three numbers is 72 the second number is three times the third the third number is eight more than the first what are the numbers

Answers

Answer:

Our three numbers are 8, 48, and 16.

Step-by-step explanation:

Let the first, second, and third numbers be x, y, and z, respectively.

The sum of them is 72. In other words:

[tex]x + y + z = 72[/tex]

The second number y is three times the third number z. So:

[tex]y = 3z[/tex]

And the third number z is eight more than the first number x. So:

[tex]z = x + 8[/tex]

To find the numbers, solve for the system. We can substitute the last two equations into the first:

[tex]x + (3z) + ( x + 8) = 72[/tex]

Substitute again:

[tex]\displaystyle x + 3(x+8) + x+8 = 72[/tex]

Solve for x. Distribute:

[tex]x+3x+24+x+8=72[/tex]

Combine like term:

[tex]5x + 32 = 72[/tex]

Subtract:

[tex]5x = 40[/tex]

And divide:

[tex]x=8[/tex]

Thus, the first number is eight.

And since the third number is eight more than the first, the third number z is 16.

The second number is three times the third. Thus, the second number y is 3(16) or 48.

Our three numbers are 8, 48, and 16.

A square has a side length of 520
meters. What is the perimeter of
the square in kilometers?

Answers

Answer: 2.08 km

Step-by-step explanation:

Side of Square = 520 m

Perimeter of Square = Side × 4

                                  = 520 × 4

                                  = 2080 m

1000 m = 1km

2080 m = 2080 ÷ 1000

              = 2.08 km

I need help with this please

Answers

Answer:

26. 35

27. 65

28. 13

Step-by-step explanation:

26. The big angle POR is given as 59 and the smaller angle inside it (POQ) is given as 24. Since the angles POQ and QOR add up to the angle POR,

QOR = POR - POQ    |     59-24 = 35

27. We are given the angles of all the smaller angles in the large angle POS. POQ, QOR and ROS are 19, 31 and 15 respectively. Since all of them add up to create the angle POS, POS = 19+31+15 = 65

28. We can use the second and third given angles (POR and POQ) to find the QOR which we can then use to find ROS. This first step is very similar to 26. We are given POR as 61 and POQ as 28, therefore QOR = 61-28 = 33

Since we now know QOR and QOS, we can repeat the process and deduct that because the two smaller angles add up to the bigger one (QOS), we can find ROS by subtracting QOR (from above) from the given QOS (46):

46 - 33 = 13

Hope this helped!

look at the image for the question?

Answers

Answer:

396 in ^3

Step-by-step explanation:

The volume of a rectangular prism is

V = l*w*h  where l is the length, w is the width, and h is the height

V = 12 * 3 * 11

V = 396 in ^3

A line is an undefined termi because it

Answers

Answer:

Goes on forever.

Step-by-step explanation:

Which of the following inequalities matches the graph?
10
6
-10
Oxs-1
Ox>-1
Oys-1
Oy 2-1

Answers

Answer:

y > -1

Step-by-step explanation:

the line is going across the y axis and is everything above -1

help asap!! will get branliest.​

Answers

Hey buddy here is your answer:-Answer:- (D)

Hope you like it please mark me as a brainliest

Answer:

5/2

Step-by-step explanation:

5^(-3). 2^2.5^6 / (2^3.5^2)

By the law of indices,

=5^(-3+6-2).2^(2-3)

=5^1.2^(-1)

=5. 2^-1

=5/2

If the area of a circle is 16π, the circumference of the circle is:

A. 8π
B. 16π
C. 2π
D. 4π

Answers

The answer is option A
Here’s the process
Hope you understand it!

A gift box shown below is packed with small cubic 1/2 inch blocks. The blocks are packed tightly with no spaces between them.
A. How many blocks are in the gift box?
B. What is the volume of the gift box?
C. Find how much wrapping paper will be needed to wrap the gift box (hint: find surface area).

Answers

Step-by-step explanation:

the box is

9 in × 3.5 in × 4.5 in = 141.75 in³

each block is

0.5 in × 0.5 in × 0.5 in = 0.125 in³ (1/8 in³)

so, we can fit

141.75 / 0.125 = 1134

blocks into the box.

and they fit neatly, as the dimensions of the box and the cubes allow a tight packing without any empty left over space in the box.

How would you find the coefficient of the third term in (x+5)^7?

Answers

Answer:

The answer is option B

Step-by-step explanation:

To find the coefficient of the third term in

[tex](x + 5)^{7} [/tex]

Rewrite the expansion in the form

[tex](a + x)^{n} [/tex]

where n is the index

So we have

[tex] ({5 + x})^{7} [/tex]

After that we use the formula

[tex]nCr( {a}^{n - r} ) {x}^{r} [/tex]

where r is the term we are looking for

For the third term we are looking for the term containing x²

that's

r + 1 = 3

r = 2

So to find the coefficient of the third term

We have

[tex]7C2[/tex]

Hope this helps you

first of all, the notation is wrong it should be [tex] {}^nC_r \text{ and more usual notation is } {n \choose k} [/tex]

second, the

[tex](r+1)^{\text{th}} \text{ term } T_{r+1} \text{ in the expansion of } (x+a)^n \text{ is } {n \choose r}x^{(n-r)}a^r[/tex]

here [tex] a=5 \text{ and } n=7 \text{ and for } 3^{\text{rd}} \text{ term } T_3, \quad r+1=3 \implies r=2 [/tex]

so the coefficient of third term is, [tex]{7 \choose 2}={7\choose 5}[/tex]

an important property of binomial coefficient you should know:

[tex] {n \choose k}={n \choose {n-k}}[/tex]

and if you interchange [tex] x \text{ and } a[/tex]

only the "order" will get reversed. i.e. the series will start from back.

another thing, the [tex] k^{\text{th}} \text{ term from beginning, is the } (n-k+2)^{\text{th}} \text{ term from behind}[/tex]

Which of the following is equivalent to –2i(6 – 7i)?

Answers

Answer:

[tex]\boxed{\sf \bf \ \ -2i(6-7i)=-14-12i \ \ }[/tex]

Step-by-step explanation:

Hello, please consider the following.

[tex]-2i(6-7i)=-12i+14i^2=-14-12i[/tex]

Hope this helps.

Do not hesitate if you need further explanation.

Thank you

Answer:

A

Step-by-step explanation:

Answer = A

The time it takes to process phone orders in a small florist/gift shop is normally distributed with a mean of 6 minutes and a standard deviation of 3 minutes. What cutoff value would separate the 2.5% of orders that take the most time to process?
A) 4.76 minutes
B) 3.52 minutes
C) 10.01 minutes
D) 11.00 minutes
E) 12.00 minutes

Answers

E) 12 minutes

A normal curve has approximately 95% of graph between mean - 2sd and mean + 2sd
So 95% of the times will be between 0 and 12 minutes. 6 - 2x3 to 6 + 2x3
2.5% will take over 12 minutes

Strangely 2.5% will also take less than 0 minutes to process which shows the normal curve is not perfect in this example.

Laura made $273 for 13 hours of work.
At the same rate, how much would she make for 17 hours of work?
sl
X
$
?
I

Answers

Laura would make $357

273/13=21
21*17=357

as
8
3) The volume of
a wall, 5 times
high as it is board and 8
times as long as it is high, 12.8
(a.metors) Find The Breadth of the
Wall​

Answers

Answer:

  0.4 meters

Step-by-step explanation:

The volume is ...

  V = LHB

  12.8 m³ = (8(5B))(5B)(B) = 200B³ . . . fill in given values

  0.064 m³ = B³ . . . . . simplify

  ∛0.064 m = B = 0.4 m

The breadth of the wall is 0.4 meters.

Find the area of the shape shown below.
2
2
nd
2
Need help Plz hurry and answer!!!

Answers

Answer:

=6 units squared

Step-by-step explanation:

area=1/2h(a+b)

        =1/2×2(4+2)

        =6

Can u pls help I don’t understand I’ll give u 15 points

Answers

Answer: [tex]\frac{4}{3}[/tex]

Step-by-step explanation:

This is a multiplication problem. You are multiplying [tex]\frac{1}{3}[/tex] by 4. This also means 4 divided by 3. They are both the same.

A multiple choice test contains 10 questions with 5 answer choices. What is the probability of correctly answering 5
questions if you guess randomly on each question?

Answers

The answer is 1/2 because there are total 10 questions. So, the probability of getting 5 correct answers is 5/10 that is 1/2.

Mark me as brainleist

Jessica just bought a refrigerator for $799. She paid $79.80 in a down payment and will pay the rest in 4 equal installments. How much does she need to pay for each installment?

Answers

Answer:

$179.80

Step-by-step explanation:

799-79.80=719. That's the down payment subtracted from the total price of the refrigerator. 719/4, since there's four equal installments, gives you 179.8. Since cents go in 10s, you make it 179.80 and slap a dollar sign in front of that.

Ax + By = C for x. plz sove

Answers

Answer:

[tex]\boxed{\boxed{ x=\frac{C-By}{A}; A\neq 0}}[/tex]

Step-by-step explanation:

[tex]Ax+By=C\\\\Ax+By-By=C-By\\\\Ax=C-By\\\\\frac{Ax=C-By}{A}\\\\\boxed{ x=\frac{C-By}{A}; A\neq 0}[/tex]

Hope this helps.

Complete the table for the given rule. Rule: y = x + 3. X ? Y 4. X ? Y 8. X ? Y 5

Answers

Answer:

X 1 for Y 4

X 5 for Y 8

X 2 for Y 5

Step-by-step explanation:

We can substitute the values of Y in the formula and then subtract three from both sides.

Evaluate the limit, if it exists. (If an answer does not exist, enter DNE.). lim h → 0 1 + h − 1 h

Answers

Answer:

1

Step-by-step explanation:

Given the limit of a function [tex]\lim_{h \to 0} \frac{(1+h)-1}{h}[/tex], to evaluate the limit, the following steps must be taken.

Step 1: Substitute h = 0 into the function given.

[tex]= \lim_{h \to 0} \frac{(1+h)-1}{h}\\\\[/tex]

[tex]= \frac{(1+0)-1}{0}\\\\= \frac{1-1}{0} \\\\= \frac{0}{0} (indeterminate)\\[/tex]

Step 2: Apply l'hospital rule

[tex]\lim_{h \to 0} \frac{\frac{d}{dh}[(1+h)-1] } {\frac{d}{dh}(h) } \\\\= \frac{0+1-0}{1}\\ \\= \frac{1}{1} \\ \\= 1[/tex]

Hence the limit of the function [tex]\lim_{h \to 0} \frac{(1+h)-1}{h} \ is \ 1[/tex]

plz someone help me with this question

Answers

Answer:

(x+3)^2=-4(y-3)

Step-by-step explanation:

(x-h)^2 = 4p(y-k)

P is the distance between the focus and vertex

P = 1 --> used distance formula for the points of -3,2 -3,3

Vertex is -3,3 --> according to picture

(x+3)^2=-4(y-3)

P is negative since it goes downwards in the picture.

Log 1/10 how do you convert this without a calculator

Answers

Answer:

  log(1/10) = -1

Step-by-step explanation:

Use the law of exponents and the meaning of logarithm.

  1/10 = 10^-1

  log(10^x) = x

So, you have ...

  log(1/10) = log(10^-1)

  log(1/10) = -1


[tex] \frac{3x - 2}{7} - \frac{5x - 8}{4} = \frac{1}{14} [/tex]

Answers

Answer:

[tex]x=2[/tex]

Step-by-step explanation:

[tex]\frac{3x-2}{7}-\frac{5x-8}{4}=\frac{1}{14}[/tex]

In order to factor an integer, we need to divide it by the ascending sequence of primes 2, 3, 5.

The number of times that each prime divides the original integer becomes its exponent in the final result.

In here,  Prime number 2 to the power of 2 equals 4.

[tex]\frac{3x-2}{7}-\frac{5x-8}{2^{2} }=\frac{1}{14}[/tex]

First, We need to add fractions-

Rule:-

[tex]\frac{A}{B} +\frac{C}{D} =\frac{\frac{LCD}{B}+\frac{LCD}{D}C }{LCD}[/tex]

LCD = [tex]7 \cdot 2^{2}[/tex]

[tex]\frac{4(3x-2)+7(-(5x-8))}{7*2^{2} } =\frac{1}{14}[/tex]

[tex]x=2[/tex]

OAmalOHopeO

Translate the statements into a confidence interval for p. Approximate the level of confidence. In a survey of 8451 U.S. adults, 31.4% said they were taking vitamin E as a supplement. The survey's margin of error is plus or minus 1%.

Answers

Answer:

The  confidence interval is  [tex]0.304 < p < 0.324[/tex]

Step-by-step explanation:

From the question we are told

      The sample proportion [tex]\r p = 0.314[/tex]

      The margin of error  is [tex]E = 0.01[/tex]

The confidence interval for  p is mathematically represented as

       [tex]\r p - E < p < \r p + E[/tex]

=>    [tex]0.314 - 0.01 < p < 0.314 + 0.01[/tex]

=>   [tex]0.304 < p < 0.324[/tex]

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The governor has some control over the final appropriations bill through the use of the ________ veto. Group of answer choices Rajah 9 menunjukkan laluan bagi kuching Fun Run. Berapakah sesaran bagi pelari tersebut? Mula 2 km 6 km Tamat 10 km Rajah Diagram 9 O A.5 km O B.6 km O c. 10 km D. 18 km Please help solve this. 10points worth it An item is regularly priced at $70. Keiko bought it on sale for 80% off the regular price. How much did Keiko pay? $ if your ans is correct i will choose you as a brainlist when the number of student of a school was increased by 30% it became 455. Find the previous number student. If g(x) = 1 - x find: -5g(4) - 1 what is a soliloquy in a drama? It can take a long time to become successful in your chosen field, however talented you are. One thing you have to be (1) _______ of is that you will face criticism along the way. The world is (2)_________ of people who would rather say something negative than positive. If youve made up your (3)_______ to achieve a certain goal, such as writing a novel, (4)_________ the negative criticism of others prevent you from reaching your target, and let the constructive criticism have a positive effect on your work. If someone says youre totally in the (5)______ of talent, ignore them. Thats negative criticism. If (6), __________, someone advises you to revise your work and gives you a good reason for doing so, you should consider their suggestions carefully. There are many film stars (7)__________ were once out of work . There are many famous novelists who made a complete mess of their first novel or who didnt, but had to keep on approaching hundreds of publishers before they could get it (8) ________. Being successful does depend on luck, to a (9)________ extent. But things are more likely to (10) ________ well if you persevere and stay positive. can someone explain this please? _____ media are specifically designed to help bring customers eyeball to eyeball with the product--often at the point of sale or close to it. factorize the expression: mn + mnp + 3mn + 3mp identifying and explaining five recommendations to address teenage pregnancy United Apparel has the following balances in its stockholders equity accounts on December 31, 2018: Treasury Stock, $650,000; Common Stock, $400,000; Preferred Stock, $1,600,000; Retained Earnings, $1,200,000; and Additional Paid-in Capital, $6,800,000. Required: Prepare the stockholders equity section of the balance sheet for United Apparel as of December 31, 2018 The length of a box is 1 cm more than its width. The height of the box is 8 cm greater than the width. The dimensions can be represented by x, x + 1, and x + 8. Multiply the dimensions and find the greatest common factor of the terms. If y varies directly with x and y = 5 when x = 4, find the value of y when x = -8 If 3sinA+4cosA=5 then find the value of cosA An operator approaching an intersection controlled by a traffic signal may proceed through a steady red light if the operator comes to a complete stop for at least ___ seconds and exercises due caution. find the equation of the line which is parallel to the line 5 x + 4y = 18 and makes an intercept of 2 units on the x-axis 2. The ratio ofthe profit, cost ofmaterials and labourin the production ofan article is 5:7:13respectively. If thecost of materials is Le840 more than that oflabour, find the totalcost of producing thearticle Which of the following equations have infinitely many solutions?Choose all answers that apply:A10x- 10 = -10x + 10B- 10x - 10 = -10x + 10C-10x 10 = -10x - 10D10x - 10 = -10x 10